Valve Cover Stamp

[skh300@xxxx]

Just an FYI, I went out and checked some valve covers from a 1955 331 Hemi in 
the garage and they both have the stamp between the #2 & #4 and #1 & # 3 
cylinders. The stamp reads as follows: USE ONLY 3/4 REACH
SPARK PLUG IN THIS 
ENGINE

Below the word engine there is a diagram of a spark plug with the measurement 
of what the reach should look like. I will try and get a good digital pic of 
it.

Steve Hildebrandt
55 C-300
Chicago, IL